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6#include <linux/fs.h>
7#include <linux/slab.h>
8#include <linux/sched.h>
9#include <linux/writeback.h>
10#include <linux/pagemap.h>
11#include <linux/blkdev.h>
12#include <linux/uuid.h>
13#include "misc.h"
14#include "ctree.h"
15#include "disk-io.h"
16#include "transaction.h"
17#include "locking.h"
18#include "tree-log.h"
19#include "volumes.h"
20#include "dev-replace.h"
21#include "qgroup.h"
22#include "block-group.h"
23#include "space-info.h"
24
25#define BTRFS_ROOT_TRANS_TAG 0
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98static const unsigned int btrfs_blocked_trans_types[TRANS_STATE_MAX] = {
99 [TRANS_STATE_RUNNING] = 0U,
100 [TRANS_STATE_COMMIT_START] = (__TRANS_START | __TRANS_ATTACH),
101 [TRANS_STATE_COMMIT_DOING] = (__TRANS_START |
102 __TRANS_ATTACH |
103 __TRANS_JOIN |
104 __TRANS_JOIN_NOSTART),
105 [TRANS_STATE_UNBLOCKED] = (__TRANS_START |
106 __TRANS_ATTACH |
107 __TRANS_JOIN |
108 __TRANS_JOIN_NOLOCK |
109 __TRANS_JOIN_NOSTART),
110 [TRANS_STATE_COMPLETED] = (__TRANS_START |
111 __TRANS_ATTACH |
112 __TRANS_JOIN |
113 __TRANS_JOIN_NOLOCK |
114 __TRANS_JOIN_NOSTART),
115};
116
117void btrfs_put_transaction(struct btrfs_transaction *transaction)
118{
119 WARN_ON(refcount_read(&transaction->use_count) == 0);
120 if (refcount_dec_and_test(&transaction->use_count)) {
121 BUG_ON(!list_empty(&transaction->list));
122 WARN_ON(!RB_EMPTY_ROOT(
123 &transaction->delayed_refs.href_root.rb_root));
124 WARN_ON(!RB_EMPTY_ROOT(
125 &transaction->delayed_refs.dirty_extent_root));
126 if (transaction->delayed_refs.pending_csums)
127 btrfs_err(transaction->fs_info,
128 "pending csums is %llu",
129 transaction->delayed_refs.pending_csums);
130
131
132
133
134
135
136
137 while (!list_empty(&transaction->deleted_bgs)) {
138 struct btrfs_block_group *cache;
139
140 cache = list_first_entry(&transaction->deleted_bgs,
141 struct btrfs_block_group,
142 bg_list);
143 list_del_init(&cache->bg_list);
144 btrfs_unfreeze_block_group(cache);
145 btrfs_put_block_group(cache);
146 }
147 WARN_ON(!list_empty(&transaction->dev_update_list));
148 kfree(transaction);
149 }
150}
151
152static noinline void switch_commit_roots(struct btrfs_trans_handle *trans)
153{
154 struct btrfs_transaction *cur_trans = trans->transaction;
155 struct btrfs_fs_info *fs_info = trans->fs_info;
156 struct btrfs_root *root, *tmp;
157 struct btrfs_caching_control *caching_ctl, *next;
158
159 down_write(&fs_info->commit_root_sem);
160 list_for_each_entry_safe(root, tmp, &cur_trans->switch_commits,
161 dirty_list) {
162 list_del_init(&root->dirty_list);
163 free_extent_buffer(root->commit_root);
164 root->commit_root = btrfs_root_node(root);
165 extent_io_tree_release(&root->dirty_log_pages);
166 btrfs_qgroup_clean_swapped_blocks(root);
167 }
168
169
170 spin_lock(&cur_trans->dropped_roots_lock);
171 while (!list_empty(&cur_trans->dropped_roots)) {
172 root = list_first_entry(&cur_trans->dropped_roots,
173 struct btrfs_root, root_list);
174 list_del_init(&root->root_list);
175 spin_unlock(&cur_trans->dropped_roots_lock);
176 btrfs_free_log(trans, root);
177 btrfs_drop_and_free_fs_root(fs_info, root);
178 spin_lock(&cur_trans->dropped_roots_lock);
179 }
180 spin_unlock(&cur_trans->dropped_roots_lock);
181
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208 spin_lock(&fs_info->block_group_cache_lock);
209 list_for_each_entry_safe(caching_ctl, next,
210 &fs_info->caching_block_groups, list) {
211 struct btrfs_block_group *cache = caching_ctl->block_group;
212
213 if (btrfs_block_group_done(cache)) {
214 cache->last_byte_to_unpin = (u64)-1;
215 list_del_init(&caching_ctl->list);
216 btrfs_put_caching_control(caching_ctl);
217 } else {
218 cache->last_byte_to_unpin = caching_ctl->progress;
219 }
220 }
221 spin_unlock(&fs_info->block_group_cache_lock);
222 up_write(&fs_info->commit_root_sem);
223}
224
225static inline void extwriter_counter_inc(struct btrfs_transaction *trans,
226 unsigned int type)
227{
228 if (type & TRANS_EXTWRITERS)
229 atomic_inc(&trans->num_extwriters);
230}
231
232static inline void extwriter_counter_dec(struct btrfs_transaction *trans,
233 unsigned int type)
234{
235 if (type & TRANS_EXTWRITERS)
236 atomic_dec(&trans->num_extwriters);
237}
238
239static inline void extwriter_counter_init(struct btrfs_transaction *trans,
240 unsigned int type)
241{
242 atomic_set(&trans->num_extwriters, ((type & TRANS_EXTWRITERS) ? 1 : 0));
243}
244
245static inline int extwriter_counter_read(struct btrfs_transaction *trans)
246{
247 return atomic_read(&trans->num_extwriters);
248}
249
250
251
252
253
254void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
255{
256 struct btrfs_fs_info *fs_info = trans->fs_info;
257
258 if (!trans->chunk_bytes_reserved)
259 return;
260
261 WARN_ON_ONCE(!list_empty(&trans->new_bgs));
262
263 btrfs_block_rsv_release(fs_info, &fs_info->chunk_block_rsv,
264 trans->chunk_bytes_reserved, NULL);
265 trans->chunk_bytes_reserved = 0;
266}
267
268
269
270
271static noinline int join_transaction(struct btrfs_fs_info *fs_info,
272 unsigned int type)
273{
274 struct btrfs_transaction *cur_trans;
275
276 spin_lock(&fs_info->trans_lock);
277loop:
278
279 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
280 spin_unlock(&fs_info->trans_lock);
281 return -EROFS;
282 }
283
284 cur_trans = fs_info->running_transaction;
285 if (cur_trans) {
286 if (TRANS_ABORTED(cur_trans)) {
287 spin_unlock(&fs_info->trans_lock);
288 return cur_trans->aborted;
289 }
290 if (btrfs_blocked_trans_types[cur_trans->state] & type) {
291 spin_unlock(&fs_info->trans_lock);
292 return -EBUSY;
293 }
294 refcount_inc(&cur_trans->use_count);
295 atomic_inc(&cur_trans->num_writers);
296 extwriter_counter_inc(cur_trans, type);
297 spin_unlock(&fs_info->trans_lock);
298 return 0;
299 }
300 spin_unlock(&fs_info->trans_lock);
301
302
303
304
305
306 if (type == TRANS_ATTACH)
307 return -ENOENT;
308
309
310
311
312
313 BUG_ON(type == TRANS_JOIN_NOLOCK);
314
315 cur_trans = kmalloc(sizeof(*cur_trans), GFP_NOFS);
316 if (!cur_trans)
317 return -ENOMEM;
318
319 spin_lock(&fs_info->trans_lock);
320 if (fs_info->running_transaction) {
321
322
323
324
325 kfree(cur_trans);
326 goto loop;
327 } else if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
328 spin_unlock(&fs_info->trans_lock);
329 kfree(cur_trans);
330 return -EROFS;
331 }
332
333 cur_trans->fs_info = fs_info;
334 atomic_set(&cur_trans->pending_ordered, 0);
335 init_waitqueue_head(&cur_trans->pending_wait);
336 atomic_set(&cur_trans->num_writers, 1);
337 extwriter_counter_init(cur_trans, type);
338 init_waitqueue_head(&cur_trans->writer_wait);
339 init_waitqueue_head(&cur_trans->commit_wait);
340 cur_trans->state = TRANS_STATE_RUNNING;
341
342
343
344
345 refcount_set(&cur_trans->use_count, 2);
346 cur_trans->flags = 0;
347 cur_trans->start_time = ktime_get_seconds();
348
349 memset(&cur_trans->delayed_refs, 0, sizeof(cur_trans->delayed_refs));
350
351 cur_trans->delayed_refs.href_root = RB_ROOT_CACHED;
352 cur_trans->delayed_refs.dirty_extent_root = RB_ROOT;
353 atomic_set(&cur_trans->delayed_refs.num_entries, 0);
354
355
356
357
358
359 smp_mb();
360 if (!list_empty(&fs_info->tree_mod_seq_list))
361 WARN(1, KERN_ERR "BTRFS: tree_mod_seq_list not empty when creating a fresh transaction\n");
362 if (!RB_EMPTY_ROOT(&fs_info->tree_mod_log))
363 WARN(1, KERN_ERR "BTRFS: tree_mod_log rb tree not empty when creating a fresh transaction\n");
364 atomic64_set(&fs_info->tree_mod_seq, 0);
365
366 spin_lock_init(&cur_trans->delayed_refs.lock);
367
368 INIT_LIST_HEAD(&cur_trans->pending_snapshots);
369 INIT_LIST_HEAD(&cur_trans->dev_update_list);
370 INIT_LIST_HEAD(&cur_trans->switch_commits);
371 INIT_LIST_HEAD(&cur_trans->dirty_bgs);
372 INIT_LIST_HEAD(&cur_trans->io_bgs);
373 INIT_LIST_HEAD(&cur_trans->dropped_roots);
374 mutex_init(&cur_trans->cache_write_mutex);
375 spin_lock_init(&cur_trans->dirty_bgs_lock);
376 INIT_LIST_HEAD(&cur_trans->deleted_bgs);
377 spin_lock_init(&cur_trans->dropped_roots_lock);
378 list_add_tail(&cur_trans->list, &fs_info->trans_list);
379 extent_io_tree_init(fs_info, &cur_trans->dirty_pages,
380 IO_TREE_TRANS_DIRTY_PAGES, fs_info->btree_inode);
381 extent_io_tree_init(fs_info, &cur_trans->pinned_extents,
382 IO_TREE_FS_PINNED_EXTENTS, NULL);
383 fs_info->generation++;
384 cur_trans->transid = fs_info->generation;
385 fs_info->running_transaction = cur_trans;
386 cur_trans->aborted = 0;
387 spin_unlock(&fs_info->trans_lock);
388
389 return 0;
390}
391
392
393
394
395
396
397
398static int record_root_in_trans(struct btrfs_trans_handle *trans,
399 struct btrfs_root *root,
400 int force)
401{
402 struct btrfs_fs_info *fs_info = root->fs_info;
403
404 if ((test_bit(BTRFS_ROOT_SHAREABLE, &root->state) &&
405 root->last_trans < trans->transid) || force) {
406 WARN_ON(root == fs_info->extent_root);
407 WARN_ON(!force && root->commit_root != root->node);
408
409
410
411
412
413
414 set_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state);
415
416
417
418
419 smp_wmb();
420
421 spin_lock(&fs_info->fs_roots_radix_lock);
422 if (root->last_trans == trans->transid && !force) {
423 spin_unlock(&fs_info->fs_roots_radix_lock);
424 return 0;
425 }
426 radix_tree_tag_set(&fs_info->fs_roots_radix,
427 (unsigned long)root->root_key.objectid,
428 BTRFS_ROOT_TRANS_TAG);
429 spin_unlock(&fs_info->fs_roots_radix_lock);
430 root->last_trans = trans->transid;
431
432
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434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451 btrfs_init_reloc_root(trans, root);
452 smp_mb__before_atomic();
453 clear_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state);
454 }
455 return 0;
456}
457
458
459void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
460 struct btrfs_root *root)
461{
462 struct btrfs_fs_info *fs_info = root->fs_info;
463 struct btrfs_transaction *cur_trans = trans->transaction;
464
465
466 spin_lock(&cur_trans->dropped_roots_lock);
467 list_add_tail(&root->root_list, &cur_trans->dropped_roots);
468 spin_unlock(&cur_trans->dropped_roots_lock);
469
470
471 spin_lock(&fs_info->fs_roots_radix_lock);
472 radix_tree_tag_clear(&fs_info->fs_roots_radix,
473 (unsigned long)root->root_key.objectid,
474 BTRFS_ROOT_TRANS_TAG);
475 spin_unlock(&fs_info->fs_roots_radix_lock);
476}
477
478int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
479 struct btrfs_root *root)
480{
481 struct btrfs_fs_info *fs_info = root->fs_info;
482
483 if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
484 return 0;
485
486
487
488
489
490 smp_rmb();
491 if (root->last_trans == trans->transid &&
492 !test_bit(BTRFS_ROOT_IN_TRANS_SETUP, &root->state))
493 return 0;
494
495 mutex_lock(&fs_info->reloc_mutex);
496 record_root_in_trans(trans, root, 0);
497 mutex_unlock(&fs_info->reloc_mutex);
498
499 return 0;
500}
501
502static inline int is_transaction_blocked(struct btrfs_transaction *trans)
503{
504 return (trans->state >= TRANS_STATE_COMMIT_START &&
505 trans->state < TRANS_STATE_UNBLOCKED &&
506 !TRANS_ABORTED(trans));
507}
508
509
510
511
512
513static void wait_current_trans(struct btrfs_fs_info *fs_info)
514{
515 struct btrfs_transaction *cur_trans;
516
517 spin_lock(&fs_info->trans_lock);
518 cur_trans = fs_info->running_transaction;
519 if (cur_trans && is_transaction_blocked(cur_trans)) {
520 refcount_inc(&cur_trans->use_count);
521 spin_unlock(&fs_info->trans_lock);
522
523 wait_event(fs_info->transaction_wait,
524 cur_trans->state >= TRANS_STATE_UNBLOCKED ||
525 TRANS_ABORTED(cur_trans));
526 btrfs_put_transaction(cur_trans);
527 } else {
528 spin_unlock(&fs_info->trans_lock);
529 }
530}
531
532static int may_wait_transaction(struct btrfs_fs_info *fs_info, int type)
533{
534 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
535 return 0;
536
537 if (type == TRANS_START)
538 return 1;
539
540 return 0;
541}
542
543static inline bool need_reserve_reloc_root(struct btrfs_root *root)
544{
545 struct btrfs_fs_info *fs_info = root->fs_info;
546
547 if (!fs_info->reloc_ctl ||
548 !test_bit(BTRFS_ROOT_SHAREABLE, &root->state) ||
549 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID ||
550 root->reloc_root)
551 return false;
552
553 return true;
554}
555
556static struct btrfs_trans_handle *
557start_transaction(struct btrfs_root *root, unsigned int num_items,
558 unsigned int type, enum btrfs_reserve_flush_enum flush,
559 bool enforce_qgroups)
560{
561 struct btrfs_fs_info *fs_info = root->fs_info;
562 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
563 struct btrfs_trans_handle *h;
564 struct btrfs_transaction *cur_trans;
565 u64 num_bytes = 0;
566 u64 qgroup_reserved = 0;
567 bool reloc_reserved = false;
568 bool do_chunk_alloc = false;
569 int ret;
570
571
572 ASSERT(current->journal_info != BTRFS_SEND_TRANS_STUB);
573
574 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
575 return ERR_PTR(-EROFS);
576
577 if (current->journal_info) {
578 WARN_ON(type & TRANS_EXTWRITERS);
579 h = current->journal_info;
580 refcount_inc(&h->use_count);
581 WARN_ON(refcount_read(&h->use_count) > 2);
582 h->orig_rsv = h->block_rsv;
583 h->block_rsv = NULL;
584 goto got_it;
585 }
586
587
588
589
590
591 if (num_items && root != fs_info->chunk_root) {
592 struct btrfs_block_rsv *rsv = &fs_info->trans_block_rsv;
593 u64 delayed_refs_bytes = 0;
594
595 qgroup_reserved = num_items * fs_info->nodesize;
596 ret = btrfs_qgroup_reserve_meta_pertrans(root, qgroup_reserved,
597 enforce_qgroups);
598 if (ret)
599 return ERR_PTR(ret);
600
601
602
603
604
605
606
607
608 num_bytes = btrfs_calc_insert_metadata_size(fs_info, num_items);
609 if (flush == BTRFS_RESERVE_FLUSH_ALL &&
610 delayed_refs_rsv->full == 0) {
611 delayed_refs_bytes = num_bytes;
612 num_bytes <<= 1;
613 }
614
615
616
617
618 if (need_reserve_reloc_root(root)) {
619 num_bytes += fs_info->nodesize;
620 reloc_reserved = true;
621 }
622
623 ret = btrfs_block_rsv_add(root, rsv, num_bytes, flush);
624 if (ret)
625 goto reserve_fail;
626 if (delayed_refs_bytes) {
627 btrfs_migrate_to_delayed_refs_rsv(fs_info, rsv,
628 delayed_refs_bytes);
629 num_bytes -= delayed_refs_bytes;
630 }
631
632 if (rsv->space_info->force_alloc)
633 do_chunk_alloc = true;
634 } else if (num_items == 0 && flush == BTRFS_RESERVE_FLUSH_ALL &&
635 !delayed_refs_rsv->full) {
636
637
638
639
640
641
642
643 ret = btrfs_delayed_refs_rsv_refill(fs_info, flush);
644 if (ret)
645 goto reserve_fail;
646 }
647again:
648 h = kmem_cache_zalloc(btrfs_trans_handle_cachep, GFP_NOFS);
649 if (!h) {
650 ret = -ENOMEM;
651 goto alloc_fail;
652 }
653
654
655
656
657
658
659
660
661
662
663
664 if (type & __TRANS_FREEZABLE)
665 sb_start_intwrite(fs_info->sb);
666
667 if (may_wait_transaction(fs_info, type))
668 wait_current_trans(fs_info);
669
670 do {
671 ret = join_transaction(fs_info, type);
672 if (ret == -EBUSY) {
673 wait_current_trans(fs_info);
674 if (unlikely(type == TRANS_ATTACH ||
675 type == TRANS_JOIN_NOSTART))
676 ret = -ENOENT;
677 }
678 } while (ret == -EBUSY);
679
680 if (ret < 0)
681 goto join_fail;
682
683 cur_trans = fs_info->running_transaction;
684
685 h->transid = cur_trans->transid;
686 h->transaction = cur_trans;
687 h->root = root;
688 refcount_set(&h->use_count, 1);
689 h->fs_info = root->fs_info;
690
691 h->type = type;
692 h->can_flush_pending_bgs = true;
693 INIT_LIST_HEAD(&h->new_bgs);
694
695 smp_mb();
696 if (cur_trans->state >= TRANS_STATE_COMMIT_START &&
697 may_wait_transaction(fs_info, type)) {
698 current->journal_info = h;
699 btrfs_commit_transaction(h);
700 goto again;
701 }
702
703 if (num_bytes) {
704 trace_btrfs_space_reservation(fs_info, "transaction",
705 h->transid, num_bytes, 1);
706 h->block_rsv = &fs_info->trans_block_rsv;
707 h->bytes_reserved = num_bytes;
708 h->reloc_reserved = reloc_reserved;
709 }
710
711got_it:
712 if (!current->journal_info)
713 current->journal_info = h;
714
715
716
717
718
719
720
721 if (do_chunk_alloc && num_bytes) {
722 u64 flags = h->block_rsv->space_info->flags;
723
724 btrfs_chunk_alloc(h, btrfs_get_alloc_profile(fs_info, flags),
725 CHUNK_ALLOC_NO_FORCE);
726 }
727
728
729
730
731
732
733
734
735
736 btrfs_record_root_in_trans(h, root);
737
738 return h;
739
740join_fail:
741 if (type & __TRANS_FREEZABLE)
742 sb_end_intwrite(fs_info->sb);
743 kmem_cache_free(btrfs_trans_handle_cachep, h);
744alloc_fail:
745 if (num_bytes)
746 btrfs_block_rsv_release(fs_info, &fs_info->trans_block_rsv,
747 num_bytes, NULL);
748reserve_fail:
749 btrfs_qgroup_free_meta_pertrans(root, qgroup_reserved);
750 return ERR_PTR(ret);
751}
752
753struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
754 unsigned int num_items)
755{
756 return start_transaction(root, num_items, TRANS_START,
757 BTRFS_RESERVE_FLUSH_ALL, true);
758}
759
760struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
761 struct btrfs_root *root,
762 unsigned int num_items)
763{
764 return start_transaction(root, num_items, TRANS_START,
765 BTRFS_RESERVE_FLUSH_ALL_STEAL, false);
766}
767
768struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root)
769{
770 return start_transaction(root, 0, TRANS_JOIN, BTRFS_RESERVE_NO_FLUSH,
771 true);
772}
773
774struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root)
775{
776 return start_transaction(root, 0, TRANS_JOIN_NOLOCK,
777 BTRFS_RESERVE_NO_FLUSH, true);
778}
779
780
781
782
783
784struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root)
785{
786 return start_transaction(root, 0, TRANS_JOIN_NOSTART,
787 BTRFS_RESERVE_NO_FLUSH, true);
788}
789
790
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794
795
796
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798
799
800
801
802
803struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root)
804{
805 return start_transaction(root, 0, TRANS_ATTACH,
806 BTRFS_RESERVE_NO_FLUSH, true);
807}
808
809
810
811
812
813
814
815
816struct btrfs_trans_handle *
817btrfs_attach_transaction_barrier(struct btrfs_root *root)
818{
819 struct btrfs_trans_handle *trans;
820
821 trans = start_transaction(root, 0, TRANS_ATTACH,
822 BTRFS_RESERVE_NO_FLUSH, true);
823 if (trans == ERR_PTR(-ENOENT))
824 btrfs_wait_for_commit(root->fs_info, 0);
825
826 return trans;
827}
828
829
830static noinline void wait_for_commit(struct btrfs_transaction *commit)
831{
832 wait_event(commit->commit_wait, commit->state == TRANS_STATE_COMPLETED);
833}
834
835int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid)
836{
837 struct btrfs_transaction *cur_trans = NULL, *t;
838 int ret = 0;
839
840 if (transid) {
841 if (transid <= fs_info->last_trans_committed)
842 goto out;
843
844
845 spin_lock(&fs_info->trans_lock);
846 list_for_each_entry(t, &fs_info->trans_list, list) {
847 if (t->transid == transid) {
848 cur_trans = t;
849 refcount_inc(&cur_trans->use_count);
850 ret = 0;
851 break;
852 }
853 if (t->transid > transid) {
854 ret = 0;
855 break;
856 }
857 }
858 spin_unlock(&fs_info->trans_lock);
859
860
861
862
863
864 if (!cur_trans) {
865 if (transid > fs_info->last_trans_committed)
866 ret = -EINVAL;
867 goto out;
868 }
869 } else {
870
871 spin_lock(&fs_info->trans_lock);
872 list_for_each_entry_reverse(t, &fs_info->trans_list,
873 list) {
874 if (t->state >= TRANS_STATE_COMMIT_START) {
875 if (t->state == TRANS_STATE_COMPLETED)
876 break;
877 cur_trans = t;
878 refcount_inc(&cur_trans->use_count);
879 break;
880 }
881 }
882 spin_unlock(&fs_info->trans_lock);
883 if (!cur_trans)
884 goto out;
885 }
886
887 wait_for_commit(cur_trans);
888 btrfs_put_transaction(cur_trans);
889out:
890 return ret;
891}
892
893void btrfs_throttle(struct btrfs_fs_info *fs_info)
894{
895 wait_current_trans(fs_info);
896}
897
898static bool should_end_transaction(struct btrfs_trans_handle *trans)
899{
900 struct btrfs_fs_info *fs_info = trans->fs_info;
901
902 if (btrfs_check_space_for_delayed_refs(fs_info))
903 return true;
904
905 return !!btrfs_block_rsv_check(&fs_info->global_block_rsv, 5);
906}
907
908bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans)
909{
910 struct btrfs_transaction *cur_trans = trans->transaction;
911
912 smp_mb();
913 if (cur_trans->state >= TRANS_STATE_COMMIT_START ||
914 cur_trans->delayed_refs.flushing)
915 return true;
916
917 return should_end_transaction(trans);
918}
919
920static void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans)
921
922{
923 struct btrfs_fs_info *fs_info = trans->fs_info;
924
925 if (!trans->block_rsv) {
926 ASSERT(!trans->bytes_reserved);
927 return;
928 }
929
930 if (!trans->bytes_reserved)
931 return;
932
933 ASSERT(trans->block_rsv == &fs_info->trans_block_rsv);
934 trace_btrfs_space_reservation(fs_info, "transaction",
935 trans->transid, trans->bytes_reserved, 0);
936 btrfs_block_rsv_release(fs_info, trans->block_rsv,
937 trans->bytes_reserved, NULL);
938 trans->bytes_reserved = 0;
939}
940
941static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
942 int throttle)
943{
944 struct btrfs_fs_info *info = trans->fs_info;
945 struct btrfs_transaction *cur_trans = trans->transaction;
946 int err = 0;
947
948 if (refcount_read(&trans->use_count) > 1) {
949 refcount_dec(&trans->use_count);
950 trans->block_rsv = trans->orig_rsv;
951 return 0;
952 }
953
954 btrfs_trans_release_metadata(trans);
955 trans->block_rsv = NULL;
956
957 btrfs_create_pending_block_groups(trans);
958
959 btrfs_trans_release_chunk_metadata(trans);
960
961 if (trans->type & __TRANS_FREEZABLE)
962 sb_end_intwrite(info->sb);
963
964 WARN_ON(cur_trans != info->running_transaction);
965 WARN_ON(atomic_read(&cur_trans->num_writers) < 1);
966 atomic_dec(&cur_trans->num_writers);
967 extwriter_counter_dec(cur_trans, trans->type);
968
969 cond_wake_up(&cur_trans->writer_wait);
970 btrfs_put_transaction(cur_trans);
971
972 if (current->journal_info == trans)
973 current->journal_info = NULL;
974
975 if (throttle)
976 btrfs_run_delayed_iputs(info);
977
978 if (TRANS_ABORTED(trans) ||
979 test_bit(BTRFS_FS_STATE_ERROR, &info->fs_state)) {
980 wake_up_process(info->transaction_kthread);
981 if (TRANS_ABORTED(trans))
982 err = trans->aborted;
983 else
984 err = -EROFS;
985 }
986
987 kmem_cache_free(btrfs_trans_handle_cachep, trans);
988 return err;
989}
990
991int btrfs_end_transaction(struct btrfs_trans_handle *trans)
992{
993 return __btrfs_end_transaction(trans, 0);
994}
995
996int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans)
997{
998 return __btrfs_end_transaction(trans, 1);
999}
1000
1001
1002
1003
1004
1005
1006int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
1007 struct extent_io_tree *dirty_pages, int mark)
1008{
1009 int err = 0;
1010 int werr = 0;
1011 struct address_space *mapping = fs_info->btree_inode->i_mapping;
1012 struct extent_state *cached_state = NULL;
1013 u64 start = 0;
1014 u64 end;
1015
1016 atomic_inc(&BTRFS_I(fs_info->btree_inode)->sync_writers);
1017 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
1018 mark, &cached_state)) {
1019 bool wait_writeback = false;
1020
1021 err = convert_extent_bit(dirty_pages, start, end,
1022 EXTENT_NEED_WAIT,
1023 mark, &cached_state);
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037 if (err == -ENOMEM) {
1038 err = 0;
1039 wait_writeback = true;
1040 }
1041 if (!err)
1042 err = filemap_fdatawrite_range(mapping, start, end);
1043 if (err)
1044 werr = err;
1045 else if (wait_writeback)
1046 werr = filemap_fdatawait_range(mapping, start, end);
1047 free_extent_state(cached_state);
1048 cached_state = NULL;
1049 cond_resched();
1050 start = end + 1;
1051 }
1052 atomic_dec(&BTRFS_I(fs_info->btree_inode)->sync_writers);
1053 return werr;
1054}
1055
1056
1057
1058
1059
1060
1061
1062static int __btrfs_wait_marked_extents(struct btrfs_fs_info *fs_info,
1063 struct extent_io_tree *dirty_pages)
1064{
1065 int err = 0;
1066 int werr = 0;
1067 struct address_space *mapping = fs_info->btree_inode->i_mapping;
1068 struct extent_state *cached_state = NULL;
1069 u64 start = 0;
1070 u64 end;
1071
1072 while (!find_first_extent_bit(dirty_pages, start, &start, &end,
1073 EXTENT_NEED_WAIT, &cached_state)) {
1074
1075
1076
1077
1078
1079
1080
1081
1082 err = clear_extent_bit(dirty_pages, start, end,
1083 EXTENT_NEED_WAIT, 0, 0, &cached_state);
1084 if (err == -ENOMEM)
1085 err = 0;
1086 if (!err)
1087 err = filemap_fdatawait_range(mapping, start, end);
1088 if (err)
1089 werr = err;
1090 free_extent_state(cached_state);
1091 cached_state = NULL;
1092 cond_resched();
1093 start = end + 1;
1094 }
1095 if (err)
1096 werr = err;
1097 return werr;
1098}
1099
1100static int btrfs_wait_extents(struct btrfs_fs_info *fs_info,
1101 struct extent_io_tree *dirty_pages)
1102{
1103 bool errors = false;
1104 int err;
1105
1106 err = __btrfs_wait_marked_extents(fs_info, dirty_pages);
1107 if (test_and_clear_bit(BTRFS_FS_BTREE_ERR, &fs_info->flags))
1108 errors = true;
1109
1110 if (errors && !err)
1111 err = -EIO;
1112 return err;
1113}
1114
1115int btrfs_wait_tree_log_extents(struct btrfs_root *log_root, int mark)
1116{
1117 struct btrfs_fs_info *fs_info = log_root->fs_info;
1118 struct extent_io_tree *dirty_pages = &log_root->dirty_log_pages;
1119 bool errors = false;
1120 int err;
1121
1122 ASSERT(log_root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
1123
1124 err = __btrfs_wait_marked_extents(fs_info, dirty_pages);
1125 if ((mark & EXTENT_DIRTY) &&
1126 test_and_clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags))
1127 errors = true;
1128
1129 if ((mark & EXTENT_NEW) &&
1130 test_and_clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags))
1131 errors = true;
1132
1133 if (errors && !err)
1134 err = -EIO;
1135 return err;
1136}
1137
1138
1139
1140
1141
1142
1143
1144
1145static int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans)
1146{
1147 int ret;
1148 int ret2;
1149 struct extent_io_tree *dirty_pages = &trans->transaction->dirty_pages;
1150 struct btrfs_fs_info *fs_info = trans->fs_info;
1151 struct blk_plug plug;
1152
1153 blk_start_plug(&plug);
1154 ret = btrfs_write_marked_extents(fs_info, dirty_pages, EXTENT_DIRTY);
1155 blk_finish_plug(&plug);
1156 ret2 = btrfs_wait_extents(fs_info, dirty_pages);
1157
1158 extent_io_tree_release(&trans->transaction->dirty_pages);
1159
1160 if (ret)
1161 return ret;
1162 else if (ret2)
1163 return ret2;
1164 else
1165 return 0;
1166}
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178static int update_cowonly_root(struct btrfs_trans_handle *trans,
1179 struct btrfs_root *root)
1180{
1181 int ret;
1182 u64 old_root_bytenr;
1183 u64 old_root_used;
1184 struct btrfs_fs_info *fs_info = root->fs_info;
1185 struct btrfs_root *tree_root = fs_info->tree_root;
1186
1187 old_root_used = btrfs_root_used(&root->root_item);
1188
1189 while (1) {
1190 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
1191 if (old_root_bytenr == root->node->start &&
1192 old_root_used == btrfs_root_used(&root->root_item))
1193 break;
1194
1195 btrfs_set_root_node(&root->root_item, root->node);
1196 ret = btrfs_update_root(trans, tree_root,
1197 &root->root_key,
1198 &root->root_item);
1199 if (ret)
1200 return ret;
1201
1202 old_root_used = btrfs_root_used(&root->root_item);
1203 }
1204
1205 return 0;
1206}
1207
1208
1209
1210
1211
1212
1213
1214
1215static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans)
1216{
1217 struct btrfs_fs_info *fs_info = trans->fs_info;
1218 struct list_head *dirty_bgs = &trans->transaction->dirty_bgs;
1219 struct list_head *io_bgs = &trans->transaction->io_bgs;
1220 struct list_head *next;
1221 struct extent_buffer *eb;
1222 int ret;
1223
1224 eb = btrfs_lock_root_node(fs_info->tree_root);
1225 ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL,
1226 0, &eb, BTRFS_NESTING_COW);
1227 btrfs_tree_unlock(eb);
1228 free_extent_buffer(eb);
1229
1230 if (ret)
1231 return ret;
1232
1233 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1234 if (ret)
1235 return ret;
1236
1237 ret = btrfs_run_dev_stats(trans);
1238 if (ret)
1239 return ret;
1240 ret = btrfs_run_dev_replace(trans);
1241 if (ret)
1242 return ret;
1243 ret = btrfs_run_qgroups(trans);
1244 if (ret)
1245 return ret;
1246
1247 ret = btrfs_setup_space_cache(trans);
1248 if (ret)
1249 return ret;
1250
1251
1252 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1253 if (ret)
1254 return ret;
1255again:
1256 while (!list_empty(&fs_info->dirty_cowonly_roots)) {
1257 struct btrfs_root *root;
1258 next = fs_info->dirty_cowonly_roots.next;
1259 list_del_init(next);
1260 root = list_entry(next, struct btrfs_root, dirty_list);
1261 clear_bit(BTRFS_ROOT_DIRTY, &root->state);
1262
1263 if (root != fs_info->extent_root)
1264 list_add_tail(&root->dirty_list,
1265 &trans->transaction->switch_commits);
1266 ret = update_cowonly_root(trans, root);
1267 if (ret)
1268 return ret;
1269 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1270 if (ret)
1271 return ret;
1272 }
1273
1274 while (!list_empty(dirty_bgs) || !list_empty(io_bgs)) {
1275 ret = btrfs_write_dirty_block_groups(trans);
1276 if (ret)
1277 return ret;
1278 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1279 if (ret)
1280 return ret;
1281 }
1282
1283 if (!list_empty(&fs_info->dirty_cowonly_roots))
1284 goto again;
1285
1286 list_add_tail(&fs_info->extent_root->dirty_list,
1287 &trans->transaction->switch_commits);
1288
1289
1290 fs_info->dev_replace.committed_cursor_left =
1291 fs_info->dev_replace.cursor_left_last_write_of_item;
1292
1293 return 0;
1294}
1295
1296
1297
1298
1299
1300
1301void btrfs_add_dead_root(struct btrfs_root *root)
1302{
1303 struct btrfs_fs_info *fs_info = root->fs_info;
1304
1305 spin_lock(&fs_info->trans_lock);
1306 if (list_empty(&root->root_list)) {
1307 btrfs_grab_root(root);
1308 list_add_tail(&root->root_list, &fs_info->dead_roots);
1309 }
1310 spin_unlock(&fs_info->trans_lock);
1311}
1312
1313
1314
1315
1316static noinline int commit_fs_roots(struct btrfs_trans_handle *trans)
1317{
1318 struct btrfs_fs_info *fs_info = trans->fs_info;
1319 struct btrfs_root *gang[8];
1320 int i;
1321 int ret;
1322 int err = 0;
1323
1324 spin_lock(&fs_info->fs_roots_radix_lock);
1325 while (1) {
1326 ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
1327 (void **)gang, 0,
1328 ARRAY_SIZE(gang),
1329 BTRFS_ROOT_TRANS_TAG);
1330 if (ret == 0)
1331 break;
1332 for (i = 0; i < ret; i++) {
1333 struct btrfs_root *root = gang[i];
1334 radix_tree_tag_clear(&fs_info->fs_roots_radix,
1335 (unsigned long)root->root_key.objectid,
1336 BTRFS_ROOT_TRANS_TAG);
1337 spin_unlock(&fs_info->fs_roots_radix_lock);
1338
1339 btrfs_free_log(trans, root);
1340 btrfs_update_reloc_root(trans, root);
1341
1342
1343 clear_bit(BTRFS_ROOT_FORCE_COW, &root->state);
1344 smp_mb__after_atomic();
1345
1346 if (root->commit_root != root->node) {
1347 list_add_tail(&root->dirty_list,
1348 &trans->transaction->switch_commits);
1349 btrfs_set_root_node(&root->root_item,
1350 root->node);
1351 }
1352
1353 err = btrfs_update_root(trans, fs_info->tree_root,
1354 &root->root_key,
1355 &root->root_item);
1356 spin_lock(&fs_info->fs_roots_radix_lock);
1357 if (err)
1358 break;
1359 btrfs_qgroup_free_meta_all_pertrans(root);
1360 }
1361 }
1362 spin_unlock(&fs_info->fs_roots_radix_lock);
1363 return err;
1364}
1365
1366
1367
1368
1369
1370int btrfs_defrag_root(struct btrfs_root *root)
1371{
1372 struct btrfs_fs_info *info = root->fs_info;
1373 struct btrfs_trans_handle *trans;
1374 int ret;
1375
1376 if (test_and_set_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state))
1377 return 0;
1378
1379 while (1) {
1380 trans = btrfs_start_transaction(root, 0);
1381 if (IS_ERR(trans))
1382 return PTR_ERR(trans);
1383
1384 ret = btrfs_defrag_leaves(trans, root);
1385
1386 btrfs_end_transaction(trans);
1387 btrfs_btree_balance_dirty(info);
1388 cond_resched();
1389
1390 if (btrfs_fs_closing(info) || ret != -EAGAIN)
1391 break;
1392
1393 if (btrfs_defrag_cancelled(info)) {
1394 btrfs_debug(info, "defrag_root cancelled");
1395 ret = -EAGAIN;
1396 break;
1397 }
1398 }
1399 clear_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state);
1400 return ret;
1401}
1402
1403
1404
1405
1406
1407
1408
1409
1410static int qgroup_account_snapshot(struct btrfs_trans_handle *trans,
1411 struct btrfs_root *src,
1412 struct btrfs_root *parent,
1413 struct btrfs_qgroup_inherit *inherit,
1414 u64 dst_objectid)
1415{
1416 struct btrfs_fs_info *fs_info = src->fs_info;
1417 int ret;
1418
1419
1420
1421
1422
1423
1424 if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1425 return 0;
1426
1427
1428
1429
1430
1431
1432
1433 record_root_in_trans(trans, src, 1);
1434
1435
1436
1437
1438
1439 mutex_lock(&fs_info->tree_log_mutex);
1440
1441 ret = commit_fs_roots(trans);
1442 if (ret)
1443 goto out;
1444 ret = btrfs_qgroup_account_extents(trans);
1445 if (ret < 0)
1446 goto out;
1447
1448
1449 ret = btrfs_qgroup_inherit(trans, src->root_key.objectid, dst_objectid,
1450 inherit);
1451 if (ret < 0)
1452 goto out;
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466 ret = commit_cowonly_roots(trans);
1467 if (ret)
1468 goto out;
1469 switch_commit_roots(trans);
1470 ret = btrfs_write_and_wait_transaction(trans);
1471 if (ret)
1472 btrfs_handle_fs_error(fs_info, ret,
1473 "Error while writing out transaction for qgroup");
1474
1475out:
1476 mutex_unlock(&fs_info->tree_log_mutex);
1477
1478
1479
1480
1481
1482
1483
1484 if (!ret)
1485 record_root_in_trans(trans, parent, 1);
1486 return ret;
1487}
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
1499 struct btrfs_pending_snapshot *pending)
1500{
1501
1502 struct btrfs_fs_info *fs_info = trans->fs_info;
1503 struct btrfs_key key;
1504 struct btrfs_root_item *new_root_item;
1505 struct btrfs_root *tree_root = fs_info->tree_root;
1506 struct btrfs_root *root = pending->root;
1507 struct btrfs_root *parent_root;
1508 struct btrfs_block_rsv *rsv;
1509 struct inode *parent_inode;
1510 struct btrfs_path *path;
1511 struct btrfs_dir_item *dir_item;
1512 struct dentry *dentry;
1513 struct extent_buffer *tmp;
1514 struct extent_buffer *old;
1515 struct timespec64 cur_time;
1516 int ret = 0;
1517 u64 to_reserve = 0;
1518 u64 index = 0;
1519 u64 objectid;
1520 u64 root_flags;
1521
1522 ASSERT(pending->path);
1523 path = pending->path;
1524
1525 ASSERT(pending->root_item);
1526 new_root_item = pending->root_item;
1527
1528 pending->error = btrfs_find_free_objectid(tree_root, &objectid);
1529 if (pending->error)
1530 goto no_free_objectid;
1531
1532
1533
1534
1535
1536 btrfs_set_skip_qgroup(trans, objectid);
1537
1538 btrfs_reloc_pre_snapshot(pending, &to_reserve);
1539
1540 if (to_reserve > 0) {
1541 pending->error = btrfs_block_rsv_add(root,
1542 &pending->block_rsv,
1543 to_reserve,
1544 BTRFS_RESERVE_NO_FLUSH);
1545 if (pending->error)
1546 goto clear_skip_qgroup;
1547 }
1548
1549 key.objectid = objectid;
1550 key.offset = (u64)-1;
1551 key.type = BTRFS_ROOT_ITEM_KEY;
1552
1553 rsv = trans->block_rsv;
1554 trans->block_rsv = &pending->block_rsv;
1555 trans->bytes_reserved = trans->block_rsv->reserved;
1556 trace_btrfs_space_reservation(fs_info, "transaction",
1557 trans->transid,
1558 trans->bytes_reserved, 1);
1559 dentry = pending->dentry;
1560 parent_inode = pending->dir;
1561 parent_root = BTRFS_I(parent_inode)->root;
1562 record_root_in_trans(trans, parent_root, 0);
1563
1564 cur_time = current_time(parent_inode);
1565
1566
1567
1568
1569 ret = btrfs_set_inode_index(BTRFS_I(parent_inode), &index);
1570 BUG_ON(ret);
1571
1572
1573 dir_item = btrfs_lookup_dir_item(NULL, parent_root, path,
1574 btrfs_ino(BTRFS_I(parent_inode)),
1575 dentry->d_name.name,
1576 dentry->d_name.len, 0);
1577 if (dir_item != NULL && !IS_ERR(dir_item)) {
1578 pending->error = -EEXIST;
1579 goto dir_item_existed;
1580 } else if (IS_ERR(dir_item)) {
1581 ret = PTR_ERR(dir_item);
1582 btrfs_abort_transaction(trans, ret);
1583 goto fail;
1584 }
1585 btrfs_release_path(path);
1586
1587
1588
1589
1590
1591
1592
1593 ret = btrfs_run_delayed_items(trans);
1594 if (ret) {
1595 btrfs_abort_transaction(trans, ret);
1596 goto fail;
1597 }
1598
1599 record_root_in_trans(trans, root, 0);
1600 btrfs_set_root_last_snapshot(&root->root_item, trans->transid);
1601 memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
1602 btrfs_check_and_init_root_item(new_root_item);
1603
1604 root_flags = btrfs_root_flags(new_root_item);
1605 if (pending->readonly)
1606 root_flags |= BTRFS_ROOT_SUBVOL_RDONLY;
1607 else
1608 root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY;
1609 btrfs_set_root_flags(new_root_item, root_flags);
1610
1611 btrfs_set_root_generation_v2(new_root_item,
1612 trans->transid);
1613 generate_random_guid(new_root_item->uuid);
1614 memcpy(new_root_item->parent_uuid, root->root_item.uuid,
1615 BTRFS_UUID_SIZE);
1616 if (!(root_flags & BTRFS_ROOT_SUBVOL_RDONLY)) {
1617 memset(new_root_item->received_uuid, 0,
1618 sizeof(new_root_item->received_uuid));
1619 memset(&new_root_item->stime, 0, sizeof(new_root_item->stime));
1620 memset(&new_root_item->rtime, 0, sizeof(new_root_item->rtime));
1621 btrfs_set_root_stransid(new_root_item, 0);
1622 btrfs_set_root_rtransid(new_root_item, 0);
1623 }
1624 btrfs_set_stack_timespec_sec(&new_root_item->otime, cur_time.tv_sec);
1625 btrfs_set_stack_timespec_nsec(&new_root_item->otime, cur_time.tv_nsec);
1626 btrfs_set_root_otransid(new_root_item, trans->transid);
1627
1628 old = btrfs_lock_root_node(root);
1629 ret = btrfs_cow_block(trans, root, old, NULL, 0, &old,
1630 BTRFS_NESTING_COW);
1631 if (ret) {
1632 btrfs_tree_unlock(old);
1633 free_extent_buffer(old);
1634 btrfs_abort_transaction(trans, ret);
1635 goto fail;
1636 }
1637
1638 ret = btrfs_copy_root(trans, root, old, &tmp, objectid);
1639
1640 btrfs_tree_unlock(old);
1641 free_extent_buffer(old);
1642 if (ret) {
1643 btrfs_abort_transaction(trans, ret);
1644 goto fail;
1645 }
1646
1647 set_bit(BTRFS_ROOT_FORCE_COW, &root->state);
1648 smp_wmb();
1649
1650 btrfs_set_root_node(new_root_item, tmp);
1651
1652 key.offset = trans->transid;
1653 ret = btrfs_insert_root(trans, tree_root, &key, new_root_item);
1654 btrfs_tree_unlock(tmp);
1655 free_extent_buffer(tmp);
1656 if (ret) {
1657 btrfs_abort_transaction(trans, ret);
1658 goto fail;
1659 }
1660
1661
1662
1663
1664 ret = btrfs_add_root_ref(trans, objectid,
1665 parent_root->root_key.objectid,
1666 btrfs_ino(BTRFS_I(parent_inode)), index,
1667 dentry->d_name.name, dentry->d_name.len);
1668 if (ret) {
1669 btrfs_abort_transaction(trans, ret);
1670 goto fail;
1671 }
1672
1673 key.offset = (u64)-1;
1674 pending->snap = btrfs_get_new_fs_root(fs_info, objectid, pending->anon_dev);
1675 if (IS_ERR(pending->snap)) {
1676 ret = PTR_ERR(pending->snap);
1677 pending->snap = NULL;
1678 btrfs_abort_transaction(trans, ret);
1679 goto fail;
1680 }
1681
1682 ret = btrfs_reloc_post_snapshot(trans, pending);
1683 if (ret) {
1684 btrfs_abort_transaction(trans, ret);
1685 goto fail;
1686 }
1687
1688 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1689 if (ret) {
1690 btrfs_abort_transaction(trans, ret);
1691 goto fail;
1692 }
1693
1694
1695
1696
1697
1698
1699
1700 ret = qgroup_account_snapshot(trans, root, parent_root,
1701 pending->inherit, objectid);
1702 if (ret < 0)
1703 goto fail;
1704
1705 ret = btrfs_insert_dir_item(trans, dentry->d_name.name,
1706 dentry->d_name.len, BTRFS_I(parent_inode),
1707 &key, BTRFS_FT_DIR, index);
1708
1709 BUG_ON(ret == -EEXIST || ret == -EOVERFLOW);
1710 if (ret) {
1711 btrfs_abort_transaction(trans, ret);
1712 goto fail;
1713 }
1714
1715 btrfs_i_size_write(BTRFS_I(parent_inode), parent_inode->i_size +
1716 dentry->d_name.len * 2);
1717 parent_inode->i_mtime = parent_inode->i_ctime =
1718 current_time(parent_inode);
1719 ret = btrfs_update_inode_fallback(trans, parent_root, BTRFS_I(parent_inode));
1720 if (ret) {
1721 btrfs_abort_transaction(trans, ret);
1722 goto fail;
1723 }
1724 ret = btrfs_uuid_tree_add(trans, new_root_item->uuid,
1725 BTRFS_UUID_KEY_SUBVOL,
1726 objectid);
1727 if (ret) {
1728 btrfs_abort_transaction(trans, ret);
1729 goto fail;
1730 }
1731 if (!btrfs_is_empty_uuid(new_root_item->received_uuid)) {
1732 ret = btrfs_uuid_tree_add(trans, new_root_item->received_uuid,
1733 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
1734 objectid);
1735 if (ret && ret != -EEXIST) {
1736 btrfs_abort_transaction(trans, ret);
1737 goto fail;
1738 }
1739 }
1740
1741 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
1742 if (ret) {
1743 btrfs_abort_transaction(trans, ret);
1744 goto fail;
1745 }
1746
1747fail:
1748 pending->error = ret;
1749dir_item_existed:
1750 trans->block_rsv = rsv;
1751 trans->bytes_reserved = 0;
1752clear_skip_qgroup:
1753 btrfs_clear_skip_qgroup(trans);
1754no_free_objectid:
1755 kfree(new_root_item);
1756 pending->root_item = NULL;
1757 btrfs_free_path(path);
1758 pending->path = NULL;
1759
1760 return ret;
1761}
1762
1763
1764
1765
1766static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans)
1767{
1768 struct btrfs_pending_snapshot *pending, *next;
1769 struct list_head *head = &trans->transaction->pending_snapshots;
1770 int ret = 0;
1771
1772 list_for_each_entry_safe(pending, next, head, list) {
1773 list_del(&pending->list);
1774 ret = create_pending_snapshot(trans, pending);
1775 if (ret)
1776 break;
1777 }
1778 return ret;
1779}
1780
1781static void update_super_roots(struct btrfs_fs_info *fs_info)
1782{
1783 struct btrfs_root_item *root_item;
1784 struct btrfs_super_block *super;
1785
1786 super = fs_info->super_copy;
1787
1788 root_item = &fs_info->chunk_root->root_item;
1789 super->chunk_root = root_item->bytenr;
1790 super->chunk_root_generation = root_item->generation;
1791 super->chunk_root_level = root_item->level;
1792
1793 root_item = &fs_info->tree_root->root_item;
1794 super->root = root_item->bytenr;
1795 super->generation = root_item->generation;
1796 super->root_level = root_item->level;
1797 if (btrfs_test_opt(fs_info, SPACE_CACHE))
1798 super->cache_generation = root_item->generation;
1799 else if (test_bit(BTRFS_FS_CLEANUP_SPACE_CACHE_V1, &fs_info->flags))
1800 super->cache_generation = 0;
1801 if (test_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags))
1802 super->uuid_tree_generation = root_item->generation;
1803}
1804
1805int btrfs_transaction_in_commit(struct btrfs_fs_info *info)
1806{
1807 struct btrfs_transaction *trans;
1808 int ret = 0;
1809
1810 spin_lock(&info->trans_lock);
1811 trans = info->running_transaction;
1812 if (trans)
1813 ret = (trans->state >= TRANS_STATE_COMMIT_START);
1814 spin_unlock(&info->trans_lock);
1815 return ret;
1816}
1817
1818int btrfs_transaction_blocked(struct btrfs_fs_info *info)
1819{
1820 struct btrfs_transaction *trans;
1821 int ret = 0;
1822
1823 spin_lock(&info->trans_lock);
1824 trans = info->running_transaction;
1825 if (trans)
1826 ret = is_transaction_blocked(trans);
1827 spin_unlock(&info->trans_lock);
1828 return ret;
1829}
1830
1831
1832
1833
1834
1835static void wait_current_trans_commit_start(struct btrfs_fs_info *fs_info,
1836 struct btrfs_transaction *trans)
1837{
1838 wait_event(fs_info->transaction_blocked_wait,
1839 trans->state >= TRANS_STATE_COMMIT_START ||
1840 TRANS_ABORTED(trans));
1841}
1842
1843
1844
1845
1846
1847static void wait_current_trans_commit_start_and_unblock(
1848 struct btrfs_fs_info *fs_info,
1849 struct btrfs_transaction *trans)
1850{
1851 wait_event(fs_info->transaction_wait,
1852 trans->state >= TRANS_STATE_UNBLOCKED ||
1853 TRANS_ABORTED(trans));
1854}
1855
1856
1857
1858
1859
1860struct btrfs_async_commit {
1861 struct btrfs_trans_handle *newtrans;
1862 struct work_struct work;
1863};
1864
1865static void do_async_commit(struct work_struct *work)
1866{
1867 struct btrfs_async_commit *ac =
1868 container_of(work, struct btrfs_async_commit, work);
1869
1870
1871
1872
1873
1874 if (ac->newtrans->type & __TRANS_FREEZABLE)
1875 __sb_writers_acquired(ac->newtrans->fs_info->sb, SB_FREEZE_FS);
1876
1877 current->journal_info = ac->newtrans;
1878
1879 btrfs_commit_transaction(ac->newtrans);
1880 kfree(ac);
1881}
1882
1883int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
1884 int wait_for_unblock)
1885{
1886 struct btrfs_fs_info *fs_info = trans->fs_info;
1887 struct btrfs_async_commit *ac;
1888 struct btrfs_transaction *cur_trans;
1889
1890 ac = kmalloc(sizeof(*ac), GFP_NOFS);
1891 if (!ac)
1892 return -ENOMEM;
1893
1894 INIT_WORK(&ac->work, do_async_commit);
1895 ac->newtrans = btrfs_join_transaction(trans->root);
1896 if (IS_ERR(ac->newtrans)) {
1897 int err = PTR_ERR(ac->newtrans);
1898 kfree(ac);
1899 return err;
1900 }
1901
1902
1903 cur_trans = trans->transaction;
1904 refcount_inc(&cur_trans->use_count);
1905
1906 btrfs_end_transaction(trans);
1907
1908
1909
1910
1911
1912 if (ac->newtrans->type & __TRANS_FREEZABLE)
1913 __sb_writers_release(fs_info->sb, SB_FREEZE_FS);
1914
1915 schedule_work(&ac->work);
1916
1917
1918 if (wait_for_unblock)
1919 wait_current_trans_commit_start_and_unblock(fs_info, cur_trans);
1920 else
1921 wait_current_trans_commit_start(fs_info, cur_trans);
1922
1923 if (current->journal_info == trans)
1924 current->journal_info = NULL;
1925
1926 btrfs_put_transaction(cur_trans);
1927 return 0;
1928}
1929
1930
1931static void cleanup_transaction(struct btrfs_trans_handle *trans, int err)
1932{
1933 struct btrfs_fs_info *fs_info = trans->fs_info;
1934 struct btrfs_transaction *cur_trans = trans->transaction;
1935
1936 WARN_ON(refcount_read(&trans->use_count) > 1);
1937
1938 btrfs_abort_transaction(trans, err);
1939
1940 spin_lock(&fs_info->trans_lock);
1941
1942
1943
1944
1945
1946
1947 BUG_ON(list_empty(&cur_trans->list));
1948
1949 list_del_init(&cur_trans->list);
1950 if (cur_trans == fs_info->running_transaction) {
1951 cur_trans->state = TRANS_STATE_COMMIT_DOING;
1952 spin_unlock(&fs_info->trans_lock);
1953 wait_event(cur_trans->writer_wait,
1954 atomic_read(&cur_trans->num_writers) == 1);
1955
1956 spin_lock(&fs_info->trans_lock);
1957 }
1958 spin_unlock(&fs_info->trans_lock);
1959
1960 btrfs_cleanup_one_transaction(trans->transaction, fs_info);
1961
1962 spin_lock(&fs_info->trans_lock);
1963 if (cur_trans == fs_info->running_transaction)
1964 fs_info->running_transaction = NULL;
1965 spin_unlock(&fs_info->trans_lock);
1966
1967 if (trans->type & __TRANS_FREEZABLE)
1968 sb_end_intwrite(fs_info->sb);
1969 btrfs_put_transaction(cur_trans);
1970 btrfs_put_transaction(cur_trans);
1971
1972 trace_btrfs_transaction_commit(trans->root);
1973
1974 if (current->journal_info == trans)
1975 current->journal_info = NULL;
1976 btrfs_scrub_cancel(fs_info);
1977
1978 kmem_cache_free(btrfs_trans_handle_cachep, trans);
1979}
1980
1981
1982
1983
1984
1985static void btrfs_cleanup_pending_block_groups(struct btrfs_trans_handle *trans)
1986{
1987 struct btrfs_fs_info *fs_info = trans->fs_info;
1988 struct btrfs_block_group *block_group, *tmp;
1989
1990 list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) {
1991 btrfs_delayed_refs_rsv_release(fs_info, 1);
1992 list_del_init(&block_group->bg_list);
1993 }
1994}
1995
1996static inline int btrfs_start_delalloc_flush(struct btrfs_fs_info *fs_info)
1997{
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007 if (btrfs_test_opt(fs_info, FLUSHONCOMMIT))
2008 writeback_inodes_sb(fs_info->sb, WB_REASON_SYNC);
2009 return 0;
2010}
2011
2012static inline void btrfs_wait_delalloc_flush(struct btrfs_fs_info *fs_info)
2013{
2014 if (btrfs_test_opt(fs_info, FLUSHONCOMMIT))
2015 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
2016}
2017
2018int btrfs_commit_transaction(struct btrfs_trans_handle *trans)
2019{
2020 struct btrfs_fs_info *fs_info = trans->fs_info;
2021 struct btrfs_transaction *cur_trans = trans->transaction;
2022 struct btrfs_transaction *prev_trans = NULL;
2023 int ret;
2024
2025 ASSERT(refcount_read(&trans->use_count) == 1);
2026
2027
2028
2029
2030
2031
2032
2033 trans->dirty = true;
2034
2035
2036 if (TRANS_ABORTED(cur_trans)) {
2037 ret = cur_trans->aborted;
2038 btrfs_end_transaction(trans);
2039 return ret;
2040 }
2041
2042 btrfs_trans_release_metadata(trans);
2043 trans->block_rsv = NULL;
2044
2045
2046
2047
2048 ret = btrfs_run_delayed_refs(trans, 0);
2049 if (ret) {
2050 btrfs_end_transaction(trans);
2051 return ret;
2052 }
2053
2054 cur_trans = trans->transaction;
2055
2056
2057
2058
2059
2060 cur_trans->delayed_refs.flushing = 1;
2061 smp_wmb();
2062
2063 btrfs_create_pending_block_groups(trans);
2064
2065 ret = btrfs_run_delayed_refs(trans, 0);
2066 if (ret) {
2067 btrfs_end_transaction(trans);
2068 return ret;
2069 }
2070
2071 if (!test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &cur_trans->flags)) {
2072 int run_it = 0;
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087 mutex_lock(&fs_info->ro_block_group_mutex);
2088 if (!test_and_set_bit(BTRFS_TRANS_DIRTY_BG_RUN,
2089 &cur_trans->flags))
2090 run_it = 1;
2091 mutex_unlock(&fs_info->ro_block_group_mutex);
2092
2093 if (run_it) {
2094 ret = btrfs_start_dirty_block_groups(trans);
2095 if (ret) {
2096 btrfs_end_transaction(trans);
2097 return ret;
2098 }
2099 }
2100 }
2101
2102 spin_lock(&fs_info->trans_lock);
2103 if (cur_trans->state >= TRANS_STATE_COMMIT_START) {
2104 spin_unlock(&fs_info->trans_lock);
2105 refcount_inc(&cur_trans->use_count);
2106 ret = btrfs_end_transaction(trans);
2107
2108 wait_for_commit(cur_trans);
2109
2110 if (TRANS_ABORTED(cur_trans))
2111 ret = cur_trans->aborted;
2112
2113 btrfs_put_transaction(cur_trans);
2114
2115 return ret;
2116 }
2117
2118 cur_trans->state = TRANS_STATE_COMMIT_START;
2119 wake_up(&fs_info->transaction_blocked_wait);
2120
2121 if (cur_trans->list.prev != &fs_info->trans_list) {
2122 prev_trans = list_entry(cur_trans->list.prev,
2123 struct btrfs_transaction, list);
2124 if (prev_trans->state != TRANS_STATE_COMPLETED) {
2125 refcount_inc(&prev_trans->use_count);
2126 spin_unlock(&fs_info->trans_lock);
2127
2128 wait_for_commit(prev_trans);
2129 ret = READ_ONCE(prev_trans->aborted);
2130
2131 btrfs_put_transaction(prev_trans);
2132 if (ret)
2133 goto cleanup_transaction;
2134 } else {
2135 spin_unlock(&fs_info->trans_lock);
2136 }
2137 } else {
2138 spin_unlock(&fs_info->trans_lock);
2139
2140
2141
2142
2143
2144
2145 if (test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state)) {
2146 ret = -EROFS;
2147 goto cleanup_transaction;
2148 }
2149 }
2150
2151 extwriter_counter_dec(cur_trans, trans->type);
2152
2153 ret = btrfs_start_delalloc_flush(fs_info);
2154 if (ret)
2155 goto cleanup_transaction;
2156
2157 ret = btrfs_run_delayed_items(trans);
2158 if (ret)
2159 goto cleanup_transaction;
2160
2161 wait_event(cur_trans->writer_wait,
2162 extwriter_counter_read(cur_trans) == 0);
2163
2164
2165 ret = btrfs_run_delayed_items(trans);
2166 if (ret)
2167 goto cleanup_transaction;
2168
2169 btrfs_wait_delalloc_flush(fs_info);
2170
2171
2172
2173
2174
2175
2176 wait_event(cur_trans->pending_wait,
2177 atomic_read(&cur_trans->pending_ordered) == 0);
2178
2179 btrfs_scrub_pause(fs_info);
2180
2181
2182
2183
2184
2185 spin_lock(&fs_info->trans_lock);
2186 cur_trans->state = TRANS_STATE_COMMIT_DOING;
2187 spin_unlock(&fs_info->trans_lock);
2188 wait_event(cur_trans->writer_wait,
2189 atomic_read(&cur_trans->num_writers) == 1);
2190
2191 if (TRANS_ABORTED(cur_trans)) {
2192 ret = cur_trans->aborted;
2193 goto scrub_continue;
2194 }
2195
2196
2197
2198
2199
2200 mutex_lock(&fs_info->reloc_mutex);
2201
2202
2203
2204
2205
2206
2207 ret = create_pending_snapshots(trans);
2208 if (ret)
2209 goto unlock_reloc;
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221 ret = btrfs_run_delayed_items(trans);
2222 if (ret)
2223 goto unlock_reloc;
2224
2225 ret = btrfs_run_delayed_refs(trans, (unsigned long)-1);
2226 if (ret)
2227 goto unlock_reloc;
2228
2229
2230
2231
2232
2233 btrfs_assert_delayed_root_empty(fs_info);
2234
2235 WARN_ON(cur_trans != trans->transaction);
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250 mutex_lock(&fs_info->tree_log_mutex);
2251
2252 ret = commit_fs_roots(trans);
2253 if (ret)
2254 goto unlock_tree_log;
2255
2256
2257
2258
2259
2260 btrfs_apply_pending_changes(fs_info);
2261
2262
2263
2264
2265 btrfs_free_log_root_tree(trans, fs_info);
2266
2267
2268
2269
2270
2271 ret = btrfs_qgroup_account_extents(trans);
2272 if (ret < 0)
2273 goto unlock_tree_log;
2274
2275 ret = commit_cowonly_roots(trans);
2276 if (ret)
2277 goto unlock_tree_log;
2278
2279
2280
2281
2282
2283 if (TRANS_ABORTED(cur_trans)) {
2284 ret = cur_trans->aborted;
2285 goto unlock_tree_log;
2286 }
2287
2288 cur_trans = fs_info->running_transaction;
2289
2290 btrfs_set_root_node(&fs_info->tree_root->root_item,
2291 fs_info->tree_root->node);
2292 list_add_tail(&fs_info->tree_root->dirty_list,
2293 &cur_trans->switch_commits);
2294
2295 btrfs_set_root_node(&fs_info->chunk_root->root_item,
2296 fs_info->chunk_root->node);
2297 list_add_tail(&fs_info->chunk_root->dirty_list,
2298 &cur_trans->switch_commits);
2299
2300 switch_commit_roots(trans);
2301
2302 ASSERT(list_empty(&cur_trans->dirty_bgs));
2303 ASSERT(list_empty(&cur_trans->io_bgs));
2304 update_super_roots(fs_info);
2305
2306 btrfs_set_super_log_root(fs_info->super_copy, 0);
2307 btrfs_set_super_log_root_level(fs_info->super_copy, 0);
2308 memcpy(fs_info->super_for_commit, fs_info->super_copy,
2309 sizeof(*fs_info->super_copy));
2310
2311 btrfs_commit_device_sizes(cur_trans);
2312
2313 clear_bit(BTRFS_FS_LOG1_ERR, &fs_info->flags);
2314 clear_bit(BTRFS_FS_LOG2_ERR, &fs_info->flags);
2315
2316 btrfs_trans_release_chunk_metadata(trans);
2317
2318 spin_lock(&fs_info->trans_lock);
2319 cur_trans->state = TRANS_STATE_UNBLOCKED;
2320 fs_info->running_transaction = NULL;
2321 spin_unlock(&fs_info->trans_lock);
2322 mutex_unlock(&fs_info->reloc_mutex);
2323
2324 wake_up(&fs_info->transaction_wait);
2325
2326 ret = btrfs_write_and_wait_transaction(trans);
2327 if (ret) {
2328 btrfs_handle_fs_error(fs_info, ret,
2329 "Error while writing out transaction");
2330
2331
2332
2333
2334 mutex_unlock(&fs_info->tree_log_mutex);
2335 goto scrub_continue;
2336 }
2337
2338 ret = write_all_supers(fs_info, 0);
2339
2340
2341
2342
2343 mutex_unlock(&fs_info->tree_log_mutex);
2344 if (ret)
2345 goto scrub_continue;
2346
2347 btrfs_finish_extent_commit(trans);
2348
2349 if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &cur_trans->flags))
2350 btrfs_clear_space_info_full(fs_info);
2351
2352 fs_info->last_trans_committed = cur_trans->transid;
2353
2354
2355
2356
2357 cur_trans->state = TRANS_STATE_COMPLETED;
2358 wake_up(&cur_trans->commit_wait);
2359
2360 spin_lock(&fs_info->trans_lock);
2361 list_del_init(&cur_trans->list);
2362 spin_unlock(&fs_info->trans_lock);
2363
2364 btrfs_put_transaction(cur_trans);
2365 btrfs_put_transaction(cur_trans);
2366
2367 if (trans->type & __TRANS_FREEZABLE)
2368 sb_end_intwrite(fs_info->sb);
2369
2370 trace_btrfs_transaction_commit(trans->root);
2371
2372 btrfs_scrub_continue(fs_info);
2373
2374 if (current->journal_info == trans)
2375 current->journal_info = NULL;
2376
2377 kmem_cache_free(btrfs_trans_handle_cachep, trans);
2378
2379 return ret;
2380
2381unlock_tree_log:
2382 mutex_unlock(&fs_info->tree_log_mutex);
2383unlock_reloc:
2384 mutex_unlock(&fs_info->reloc_mutex);
2385scrub_continue:
2386 btrfs_scrub_continue(fs_info);
2387cleanup_transaction:
2388 btrfs_trans_release_metadata(trans);
2389 btrfs_cleanup_pending_block_groups(trans);
2390 btrfs_trans_release_chunk_metadata(trans);
2391 trans->block_rsv = NULL;
2392 btrfs_warn(fs_info, "Skipping commit of aborted transaction.");
2393 if (current->journal_info == trans)
2394 current->journal_info = NULL;
2395 cleanup_transaction(trans, ret);
2396
2397 return ret;
2398}
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root)
2411{
2412 int ret;
2413 struct btrfs_fs_info *fs_info = root->fs_info;
2414
2415 spin_lock(&fs_info->trans_lock);
2416 if (list_empty(&fs_info->dead_roots)) {
2417 spin_unlock(&fs_info->trans_lock);
2418 return 0;
2419 }
2420 root = list_first_entry(&fs_info->dead_roots,
2421 struct btrfs_root, root_list);
2422 list_del_init(&root->root_list);
2423 spin_unlock(&fs_info->trans_lock);
2424
2425 btrfs_debug(fs_info, "cleaner removing %llu", root->root_key.objectid);
2426
2427 btrfs_kill_all_delayed_nodes(root);
2428
2429 if (btrfs_header_backref_rev(root->node) <
2430 BTRFS_MIXED_BACKREF_REV)
2431 ret = btrfs_drop_snapshot(root, 0, 0);
2432 else
2433 ret = btrfs_drop_snapshot(root, 1, 0);
2434
2435 btrfs_put_root(root);
2436 return (ret < 0) ? 0 : 1;
2437}
2438
2439void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info)
2440{
2441 unsigned long prev;
2442 unsigned long bit;
2443
2444 prev = xchg(&fs_info->pending_changes, 0);
2445 if (!prev)
2446 return;
2447
2448 bit = 1 << BTRFS_PENDING_COMMIT;
2449 if (prev & bit)
2450 btrfs_debug(fs_info, "pending commit done");
2451 prev &= ~bit;
2452
2453 if (prev)
2454 btrfs_warn(fs_info,
2455 "unknown pending changes left 0x%lx, ignoring", prev);
2456}
2457